Add features to existing 'finger painting' android app

I have an android app with which you can do finger paint basically you can select different colors and draw on a drawing view/canvas with different sizes of the pen. You can also erase, undo, redo, save, share, fill background color, etc. I need an individual who has experience on java based android app development and has worked on canvas, paint, drawing, pinch zoom etc features. I need new features to be added to this app which mainly include the below things. 1. Add capability to pinch-zoom what is currently drawn on the canvas and scale appropriately, user should be able to draw in zoomed view as well scaling the selected pen size according to the current zoom level. 2. Add capability to draw shapes like line/rectangle/circle/square/star etc which can be resized which drawing them. 3. Ability to fill the closed areas on the drawn with the help of existing fill background/area feature. 4. Ability to add at least 3 more layers of drawing view/canvas which when combined create a final drawing. 5. Add capability to mix colors or add saturation level. 6. Add capability to select different types of brush and their sizes. 7. Resolve top two ANR/crash issues. How we will work: - You'll be provided a GitHub repo and added as a contributor - for each feature change you'll have to create a pull request and share it for approval - for each feature you'll have to explain what was done before the PR merge via meetings (basically knowledge transition) - you can refer to this app on the play store (looking to implement some of the similar features if not all in our app) search for 'Pocket Paint catrobat'